As packet-based networks evolve, network elements such as routers are beginning to perform services in addition to packet forwarding services. Services provided by routers may be supported in a virtualized manner and, hence, may result in multiple service instances of any given service. Hence, each user or customer of a router may be allocated resources that are needed to provide the given service or, more specifically, resources needed to support an instance of the given service. Efficiently allocating the resources increases the likelihood that assured service levels may be maintained by a service provider.